As the Sochi Games begin it is worth remembering that two of the most important political moments in Olympic history have followed failed boycott attempts (World authors join protest against Putin, 6 February). In 1936 the American Athletic Union, repulsed by Nazi Germany's treatment of its Jewish citizens, collected over half a million signatures in favour of boycotting the Berlin Games. Only reassurances from Avery Brundage, antisemite and future IOC president, ensured American – and thereby Jesse Owens's – participation. The story of Owens is complex, but his achievement is commonly remembered as a demolition of Hitler's claims to Aryan superiority.

Similarly in 1968, athletes in the US called unsuccessfully for a boycott under the banner of the Olympic Project for Human Rights. Two of the most outspoken athlete-activists, Tommie Smith and John Carlos, would raise clenched-fist salutes on the medal rostrum in a powerful statement against racism and poverty. Vilified by many at the time, their dignified protest remains one of the most iconic images of the 20th century. With no boycott campaign materialising, Sochi offers athletes a unique opportunity to register disgust at Putin's treatment of the LGBTQ community in Russia. Any athlete who finds the courage to do so will achieve a legacy that resonates far beyond their sporting success.Gareth EdwardsPortsmouth, Hampshire

• Stephen Fry and other celebrities have rightly drawn attention to the dreadful treatment of gays in Russia. Russia, however, does not have the death penalty. The other superpower does (US executes 14th woman since 1976, 6 February). Recently a man was executed by lethal injection in Ohio. It took him 15 minutes to die. Some 3,000 are on death row, many have been there for half a lifetime. Yet not a squeak of protest, as far as I can tell, from our celebrities.Ian JonesLondon